Koso REXA Electraulic Xpac, Installation And Operation Manual

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REXA
Electraulic Actuators & Drives
Xpac
Installation Manual -- Version 5.1 (5/08)
13
4 MECHANICAL INSTALLATION
The Xpac can operate any device requiring force and stroke or
torque and rotation within its range. These include louvers, dampers,
variable speed drives and valves. While the instructions below are
primarily focused on valves, they also apply to any device that may
be controlled by the
Xpac .
4.1 R Series (Rotary)
Unless otherwise specified, R Series actuators are shipped with a
four bolt mounting pattern and female key (fail in place) or male key
(spring failure) stem connection. Alternatively,
REXA
can provide
custom mounting components to adapt to the device being controlled.
Contact your sales representative for more details.
4.1.1 Fail In Place Installation
With the actuator separated from its mounting, rotate the valve shaft
to the closed position. Move the actuator in the same direction until
the end of rotary piston travel is reached. If the optional handwheel is
not available, remove the motor cover and directly rotate the outboard
end of the motor shaft. The connection between the driven device and
the actuator should be within 2° to 4°. If a large discrepancy exists
between the mating connections, the adapter may be incorrect.
4.1.2 Universal Rotary Spring Failure
CAUTION!
REXA actuators, denoted by an E, R or U in the
model number, contain a spring under tension. Fail-
ure to properly remove this force before disassembly
can cause serious injury to maintenance personnel.
Contact REXA for disassembly instructions.
The universal rotary spring package is a bolt on addition to the
REXA
R series actuator. The unit may rotate in either a clockwise or coun-
terclockwise direction upon power loss. To complete this feature, a
normally open solenoid valve is installed in the power module and
usually wired to the input power. Please refer to Technical Memo
4, Spring Failure, for available sizes.
The spring package will be pre loaded (compressed) to a specified
torque as indicated on the order. The pre loaded torque is set at an
angle of 45° to the spring axis. Installation of the driven device
Most rotary valves rely on position to
shut off and do not require additional
seating torque beyond that required to
operate against the pressure drop and
to overcome friction. Exceptions in-
clude rotary eccentric plug type valves
and elastomer lined butterfly valves.
For these valves, apply additional
rotation in the closed position to insure
sufficient seating torque.
!
If the spring tension must be released,
make note of the initial compression
(distance) to insure correct output
torque upon reassembly.
Installation of an accumulator failure
is explained in Appendix G.